Hello new here. I recently bought a Tarmac Sl8 frame set that I will let build. I was controlling all the pieces that I need and I saw that I will need also a headset expander that will take space inside the fork. I was checking my fork and I see that there is already a kind of expander but it seems stuck in the fork. My question is, is it this normal and second will I need to let remove it and use a normal headset expander? Thank you anyway for the help and sorry if it seems a stupid question 🙂
by sultano792
11 Comments
What is currently installed is a star nut. Option 1. Use that. Option 2 use a punch and hammer it through and use something else. If you use option 1 get a bike shop ro set it in a little deeper in the steer tube. It s important to get it set in there straight.
Is that a carbon or aluminum steerer tube? What you have there is a star nut, should be only used in metal steerers.
whoever did this – probably wanted a rider to die
carefully remove it and try not to crack the tube during the process.
a proper expander is something like a fouriers HA-S005-NT
That’s a steel star nut and it’s not to be used in carbon steer tube.
It should be removed and replaced with proper expander as others have stated.
Do not ride until that is out.
Honestly, it could be cooked.
if it’s already in there, leave it.. I personally wouldnt use that nut for anything more than initial preloading of the fork bearings, and remove the preload tension once set. that star nut will chew into the carbon and cause issues. dont mount anything like a computer or anything that would rely on this for mounting. It might be useable for quite sometime. but, carbon forks, steerertubes and so on flex quite a bit under riding conditions, so that star nut might still chew up the steerer tube. I would replace that fork sometime in the future. How did that nut get in there in the firstplace?
You can try to drill through the middle of the star nut to destroy and get it out.
According to Park Tools’ article [Star Fangled Nut and Expansion Plug Installation](https://www.parktool.com/en-int/blog/repair-help/star-fangled-nut-and-expansion-plug-installation), “Well… a star nut is not designed to be removable.”
Watch the video to see what you’re up against. Some contributors to the bikewrench thread [Carbon steerer tube with star nut?](https://www.reddit.com/r/bikewrench/comments/sqr67y/carbon_steerer_tube_with_star_nut/) say that’s a bad idea because it can cause cracking.
Some replies suggest drilling through the nut. Hmmm. I’m not sure that’s a great idea. The “leaves” of that nut are made of hardened and tempered spring steel designed to marginally bite into the inside of a metal steerer tube. If you try to drill it there is a very good chance of the drill snagging as it breaks through which could cause the whole thing to spin inside the steerer acting like a mini circular saw cutting into the much softer carbon. Drilling might work but use a series of drill bits each slightly bigger than the last with a drill with good speed control on the trigger.
Edit: and use a bit of coolant to stop overheating
I would see if you can cut that part of the steerer off and lower your stem. That is unsafe now.Â
Not easy.
I would drill three holes in the wing and then bend the wing. To steer the drill, I would make a hole in a small metall piece. I can then hold the metal piece with a plier until the drill bit bites. After I have bent three wings, the nut probably gets out.
You can probably find a plier to bend with at your hardware store. Don’t be afraid to grind on the plier.
New Fork Day.
Hooray!